Stereoscopic plotter



Nov. 25, 1941. '.1. E. KING ETAL 2,263,971

I -sITEREoscoPIc PLOTTER Filed June 17, 1941 5 Sheets-Sheet l lo gl I INVENTORS JASPER E. KING JOHN W. ELLIOTT BY Y PHILIP B. KAIL -f @y ATTORNEYS Nov. 25, 1941. 1E, KING ETAL 2,263,971

STEREOSCOPIC PLOTTER Filed June 17, 1941 5 Sheets-Sheet 2 @V151 15221" 15e K 157@ 1 @NW1-- v 1NvENToRs` JASPER E. KING JOHN w.1-:1 L10TT MMM-J TTOR N EYS 5 Sheets-Sheet 5 Filed June 17, 1941 mmv INVENTORS JASPER E. KING JOHN w. ELLIOTT PH1L|PF`B. KAN.

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.91 I? ATTORNEYS Nov. 25, 1941. J. E. KING ETAL STEREOSCOPIC PLOTTER Filed June 17, 1941 5 Sheets-Sheet 4 INVENTORS JASPER E. KING JOHN W. ELLIOTT A. TQRNEYS Nov. 25, 1941. J, E Kmq; E+ AL. 2,263,971

STEREOSCOPIC PLOTTER Filed June 1'7, 1941 5 Shee'lis-Sheel 5 \Nv ENT oRs JASPER EKING JOHN w,ELl |oTT Pp-HUP B.| A|L 70( Patented Nov. 25, 1941 2,263,971 ICE- 'STEREOSCOPIC PLOTTER Jasper E. King, John W. Elliott, and Philip B.`

Kal, Denver, Colo., assignors to Claude R. Wickard, as Secretary of Agriculture oi' the United States of America, and his successors in oice Application June 17, 1941, sel-1an No. 398,442

(ci. SL24 (Granted under the act oi' March 3, 1883, as

` amended April 30, 1928; 370 0. G. 757) 13 Claims.

This application is made under the4 act of March 3, `1883, as amended by theact of. April 30, 1928, and the invention herein described and claimed, if patented, may be manufactured and used by or for the Goverment ofthe United States of America for governmental purposes without the payment to us of any royalty thereon.

This invention relates to photogrammetry gen` erally and the principal object is the provision of an instrument in which vertical photographs can be viewed stereoscopically and maps fabricated giving the topography and planimetry of the model viewed. Such instruments are generally referred to as stereoscopic plotters.

The general object of this invention is the provision of an instrument of the type mentioned which is simple and inexpensive in construction as compared to instruments of a similar nature for accomplishing a similar objective.

Another object of .this invention is the provision of an instrument which will permit the fab- Figure 1 is a front elevational view illustrating the general arrangement of parts of an embodiment of our invention, partly broken away.

Figure 2 is a section along the line 2-2 of Figure 1 with parts in the background broken away.

Figure 3 is a plan view.

Figure 4 is a plan section along the line 4-4 of Figure 1,

Figure 5 is a section along the line 5--5 of Figure 4.

Figure 6 is a section along the line 8-8 of Figure 4.

Figure 7 is a plan view of the index marks and supporting bar.

Figure 8 is a section along the line 8-8 of Figure 2|.

f Referring with more particularity to the drawings in which like numerals designate likev parts, the embodiment illustrated comprises a suitable housing 2|, including end walls 22 and 23, a base 24, and a rear wall 25. A removable cover (not shown) for the remaining exposed portion of ,the housing may be provided to completely enclose the instrument therein when not in use. A portion 28 of the base 24 is cut away to permit the tracing implement of the instrument to be any plane surface upon which the instrument may rest.

Within the housing 2| there is mounted near the top a mirror stereoscope comprising the usual eye pieces 21 and 28 and eye piece mirrors 28 and 30 and wing minors 3| and 32. The -mirrors 3| and 32 are mounted on a. pair of parallel bars 33 and 34, whichbars are horizontally xed, one above the other, to the end walls 22 and 23 of the housing. The mirrors 28 and 38 are comounted with the eye pieces 21 and 28 in a frame 35 on a bracket 38 having a sleeve 31 slidable on the upper bar 33. Head rests 38 and 38 above the eye pieces 21 and 28 are adJustably secured to the bracket 38.

An abutment screw 48 is threaded through the bracket 38 to abut the lower bar 34. By adjusting the position oi' this screw, the frame 35 can be tipped around the bar 33 for the purpose of leveling the leye piece mirrors 28 and 38.

Adjustment of the frame 35 along the bar 33 is accomplished by means of a rider 4| on the bars 33 and 34, adjustably clamped on the bar 33 by means of a set screw 4|A, which rider carries a micrometer Vscrew 42 parallel to the bar 33. One end of the screw 42 carries a thumb grip 43, the other end being threadedly" engaged with the bracket 38. I

The wing mirrors 3| and 32 are mounted on brackets 48 and 41, said brackets .being vertically pivoted to sleeves 48 and 48, said sleeves being slidably mounted on the bar 33. Sleeves 48 and 49 carry arms 58 and 5|, which arms l51, at the center of which short upright pins 58 and 53 are fixed to engage pivotally the centers of the photographic prints. Each of these platens is fixed to convex runners and 8| disposed in vertical parallel planes, which are supported on corresponding concave shoulders 82 and 83 of a block 84 and held in position by abutments 85 and 86 integral with the block 84 and bearing against the inner sides oi the runners 88 and 8|. The inner sides of the runners are provided with notched grooves and the sides of the abutments contacting the runners have projections 85A and 88A complementary with said grooves, thereby holding the runners down against the shoulders 82 and 83. r

The bottom of the block 84 is provided with convex runners 81 and 88 similar to the runners 88 and 8| which are disposed in vertical planes 90 to the runners 80 and 8|.

These runners`8`|v lowered in contact with and to be moved over 60 and 88 are similarly seated on concave shoulders the phototables 54 and 55 to move upwardly to' 69 and 10 of a base 1|, against which shoulders they are held by means of tapered abutments 12 and 13 similar to the abutments 65 and 66. -The base 1| of one of the phototables- 55 is fixed to the horizontal arm 14 of an angle bracket 15 Vand the base 16 of the other phototable 54 is fixed gether, and rotation in the opposite direction of to the horizontal arm 16A of a similar angle bracket 11. The brackets 11 and 15 carry vertical sleeves 16 and 19 which ride on vertical posts -80 and 8| fixed adjacent the end walls 22 and 23 within the housing 2|. The sleeves 18 and 19 are provided with anti-friction rollers 82 and 83 which contact and roll on posts 80 and 8|.` In order to lock the phototables in different positions along the` posts 80 and 8|, clamps 84 and 85 attached to the brackets 15 and 11 are provided. y

An arced rack 86 is fixed to the bottom of each of the platens 56 and'51 parallel to the runners 60 and 6| and 'engages a worm 81 which is fixed to the end of a shaft 88 rotatablyV mounted on the block 64. The other end of said shaft projects outwardly and is provided with a knurled knob 89 to facilitate manual rotation.

Similarly, a curved rack 90 is integral with the bottom ofthe block 64 parallel to the runners 61 and 68 'and engages a worm 9| fixed to one end of a shaft 92, said shaft being rotatably m'ounted on the base-member 1|. shaft projects outwardly and is provided with a knurled knob 93 to facilitate manual rotation thereof. The centers of curvature of runners 60 and 6| areat a distance above the plane of the platens equal to the-focal point of the stereoscopic pictures to be used o n the instrument. The centers of curvature of the runners 61 and 68 are at the same distance above the platens.

The phototables 54 and 55 are held rigidly together by means of a stiff bar 94 fixed to the bases 1| and 16. Illuminating lamps 95v and 96 are mounted on the bar 94 to illuminate photographs placed on the platens 56 and 51.` However, these lamps may be mounted at any other suitable' place in the housing.

The ph ototables 54 and 55 are movedvertically said hand wheel causes the phototables to move downwardly. The weight of the phototables and of the parts movable therewith are counterbalanced by means of coil springs ||5 and ||6 which are mounted for tensioningaround shaft |06 adjacent the ends of sleeve ||0-. One of the ends of springs ||5 and |,I6 is fixed to sleeve ||0 and the other end anchored to a fixed point of the instrument.

Between the wing mirrors 3| and 32 and the phototables 54 and 55 there are disposed index marks of any suitable design, but preferably simple dots ||1 and ||8 inscribed, etched, or otherwise provided on glass discs ||-9and |20, or other suitable transparent material. The discs ||9 and |20 are mounted i-nl frames |2| 'and |22, which frames are xed to brackets |23 and |24 slidable on the ends of a horizontal bar which is in a vertical plane parallel to the line of centers of the platens 56 and 51. Set screws |26 and |21 are provided through the brackets |23 and |24 for clamping them in different positions along the bar |25. On one end of the bar |25 a collar |28 is adjustably clamped, which carries a micrometer screw |29 having on one end a x knurled head |30 for manually rotating it, the

along the posts 80 and 8| by a hand wheel 91 on one side of the instrument which` is fixed to one end of 'a rotatable shaft 98 mounted through a bearing 99 in one of the end walls 22 or 23 depending on whether the machine is to be used by a righthanded operator or a left-handed operator. The

other end of the shaft 99 is fixed to a spiral gear |00 which 'meshes with another spiral gear |0| to which there is fixed one end of a-shaft |02 extending rearward within the housing 2|. The

gears |00 and |0| are housed in a gear box` |03. The rearward end of the shaft |02 is fixed to a worm |04 which meshes with a. Worm gear |05 on the end of a horizontal shaft |06. The gears |04 and |05 are housed by gear box |01. The shaft |06 is rotatably mounted in bearings |08 and |09 on the end walls 22 and 23. About the shaft' |06 a sleeve ||0 is disposed, to the ends of which there are fixed arms and ||2. The shaft |06 and sleeve ||0 are made co-actable by means of a pin I3 midway between the arms and I2, driven through'both the sleeve ||0 and shaft |06. In this manner torque displacement is distributed equally to both arms and ||2 when the shaft |06 is rotated.

The outer ends of theV arms and ||2 are pivoted to one of the ends of links ||3 and ||4, 'the other end of' each link being pivoted to its corresponding sleeve 18 and 19. By-these means rotation of hand wheel 91 in one direction causes -top of stanchions |3|.

other end being threadedly engaged with the adjacent index mark bracket. The bar |25 is supported parallel to phototables 54 and 55 on the These stanchions are'carried on a support |32 which is movable over the cut-out portion 26 of the base of the instrument. The support |32 is pivoted to a vertical pin '|33 fixed to the fork branches |34' and |35 of thebifurcated end of Aan arm |36, said branches straddling the support |32, substantially as shown. The other end of the arm |36 is pivoted to a verltical pin |31 which pin is fixed to fork branches |38 and |39 of the bifurcated end of another arm |40. The other end of the arm |40 is pivoted to a pin |4| vertically fixed to a bracket |42 on the base of the instrument. u

The pin |31 extends through the lower branch |39 of the arm |40 and is fixed to the center of a horizontal cross arm or X-shaped member |43, one.pair of opposite arms |44 and |45 of said member being in a vertical plane parallel to the bar |25. The outer ends of the arms 44 and |45 are pin-connected to the ends of a pair of links |46 and |41 of equal length, the point of connection on sad arms |44 and |45 beingequidistant from lthe axis of pin |31. The other end of the links -|46 an'd |41 is pin-connected to the support |32 on opposite sides of and equidistant from the pin |33 to form a parallelogram linkage.

The other arms |48 and |49 of the member |43 also have theirV outer ends pin-connected to the ends of a pair of links |50 and |5| of equal length,

' the points of connection on said arms |48 and |49 'I'he other ends of the links |50 and |5| are pin.

connected to the bracket |42 on opposite sides of -and equidistant from the pin |4| to form another parallelogram linkage. Byl these means the bar |25 and index marks ||1 and I8 are constrained to move in ahorizontal plane p arallel to the line of centers of the platens 56 and 51.

A pencil, pen, stylus, or other tracing implement |52 is attached to the bottom of a post |53 whichpost is slidably and rotatably mounted through the bracket |32 and carries a weight |54 at the top to press the tracing implement against the working plane. The operator moves the tracing implement by means of a handle 154A horizontally hinged to the post |53.

A vertical scale |55 is mounted adjacent to one of the posts 80 and 8l, say the` post 80, and a pointer |56 movable over the scale |55 is fixed to the bracket 11. In view of the fact that the viewing distance of the instrument varies in operation and thereby causes the model to become elongated and depressed, the graduations of the scale |55 are not uniform but represent the relation between intervals of ground elevation and intervals of movement of the `.phototables corresponding to the same ground intervals. These graduations can be determined either empirically or by mathematical calculation.

The entire instrument is supported on casters |51 to permit easy movement over a mapping surface |58.

The instrument is operated as follows: A pair of vertical photograph prints having a stereoscopic overlap is mounted on the platens 56 and 51 with the center of each print over the center of each platen. The prints are heldin this position by forcing the pins 58 and 59 through the center of the print. The prints are then oriented about the pins until they are in v stereoscopic `correspondence and then clamped L. map table by the tracing implement.

mapping surface. The tracing implement is then moved so that the oating mark. at the height setting of the phototables constantly contacts the model at each change of position. In this manner the iioating mark follows a line of constant elevation which is traced on the When one contour line has` been mapped, the height setting of the phototables is changed by turning the hand wheel 91 until the pointer |56 is opposite the point on the scale |55 indicating the next contour elevation desired and the procedure is repeated. This is done for each to platens by clips, Scotch tape, or any othersuitable means.

The stereoscopic in the usual mannerby the use of basic reference points obtained from ground control, 'the adjustments being made by tipping and tilting the platens with the knobs 89 and 93, the while maintaining stereoscopic correspondence. vIn using the instrument for planimetry, it is not essential to horizontalize the model, although it is preferred. The instrument is then adjusted for a selected scale by spreading the index marks to a position where the movement of their fused images as seen through the stereoscope, commonly referred to as the floating mar between two given points on the model is equal to the movement of the tracing implement |52 between the same two points plotted to the desired scale on the mapping surface |58.

In making planimetrie maps, the index marks are moved to a position where the floating mark appears to contact the surface of the model at a point on the extreme end of a planimetric line, such as a drainage' line, and the tracing implement is put in contact with a mapping surface over which the instrument is placed. The tracing implement is then moved so that the floating mark follows the selected planimetrie line of themodel, the while continually changing the elevation of the phototables by turning the hand wheel 91 to cause the floating mark to appear to contact the surface of the' model at every point along the planimetrie line traversed. When this traverse is completed, the tracing implement is elevated and another planimetric line is selected for which the same procedure is followed. This is repeated for -every desired planimetrie line of the stereoscopic model to complete the map.

To use the instrument for making contour maps, the same preliminary adjustments are made as indicated above, including horizontalization of the model. The phototables are then set at a height so that the floating mark appears to contact the model at a point on a selected contour elevation thereof and the tracing implement is placed in contact with the model is. then horizontalized contour until the map is completed.

Having thus described our invention, we claim:

1. A mapping instrument comprising a portable housing movable on a mapping surface, said housing containing a pair of tables for mounting stereoscopic pictures, means for moving said tables vertically, a stereoscope over said tables for stereoscopically viewing pictures on said tables, index marks supported for horizontal movement between said tables and said stereoscope in the field of stereoscopic vision, means constraining the movement of said marks in a horizontal plane parallel to the line of centers of said tables', and atracing implement comovable with said index marks for tracing lines on said mapping surface in accordance with the movements of said yindex marks.

2. A mapping instrument comprising a portable housing movable on a mapping surface, said housing containing a pair of tables for mounting stereoscopic pictures, means for moving said tables vertically, means for independently tipping and tilting said tables about a point thereabove, a stereoscope over said tables Yfor stereoscopically viewing pictures on said tables, index marks supported forv horizontal movement between said tables and said stereoscope in the field of stereoscopic vision, means constraining the movement of said marks in a horizontal plane parallel lto the line of centers of said tables, and atracing implement comovable with vsaid index marks for tracingv lines on said mapping surface in accordance with the movements of said index marks.

3. A mapping instrument comprising a portable housing movable on a mapping surface, said housing containing a pair of tables for mounting stereoscopic pictures, means for moving said tables vertically, a pointer vertically co-movable with said tables and a vertical scale adjacent said pointer designating intervals of ground elevation corresponding to the vertical movement of said tables, a stereoscope over said tables for stereoscopically viewing pictures on said tables, index marks supported for horizontal movement between said tables and said stereotables vertically, a stereoscope forA viewing pictures on said tables, a'pair of index marks above said table in the eld of view of said stereoscope, said marks being spaced in the direction of the line of centers of said tables and at a fixed dis- 5. In amapping instrument of the character.

described having in a portable housing a pair of tables -for mounting stereoscopic pictures, vertical center pins for engaging said pictures as 9. In a plotting device having tables for mount ing stereoscopic pictures and a stereoscope for viewing pictures on said tables, index marks comovable in a horizontal plane between the stereoscope and the tables, a tracing implement movable with said index marks, means for raising and lowering said tables, lamps co-movable with' said tables for illuminating pictures mounted thereon, and means for constraining. the 'movements of said index marks so that every position of said marks is parallel to every other position a pivot, means for independently tipping and tilting said tables, means for coemoving said tables vertically, a pair of index marks above said tables, a `stereoscope for viewing said pictures and said marks stereoscopically at the same time, supporting means for said marks and a linkage for constraining the movement of said marks in a horizontal plane so that every position of said marks is parallel to every other position, and a tracing implement co-movable with said marks for tracing lines on a surface in accordance with the movement of said marks.

6. In a mapping device of the character described having in a portable housing a pair of tables for mounting stereoscopic pictures, brackets supporting said tables, vertical posts slidably engaging said brackets, means for holding said brackets in substantially the same horizontal plane, a horizontal shaft rotatably mounted in the housing, a sleeve about said shaft, means connecting the center of said shaft with the center of said sleeve, arms secured to the ends of said sleeve projecting toward said brackets, links connecting the outer ends of said arms with said brackets, springs mounted for tensioning about said shaft between the ends of said sleeve and said housing to counterbalance the weight of said tables and parts movable therewith, and means for rotating said shaft to raise and lower said tables.

7. In a mapping device having a table for mounting a stereoscopic picture, said table comprising a platen for mounting the picture, a vertical pin on said platen for pivotally engaging the picture, curved runners secured to. said platen, said runners being in parallel vertical planes, a block having shoulders complementary to said runner, means for holding said runner in slidable engagement with said shoulders, similar curved runners secured to said block in parallel vertical planes perpendicular to the planes of said first-mentioned runners, a base support having shoulders complementary to said block runners, means for holding said block runners in slidable relation with said base support shoulders, and means for controllably actuating all of said runners on their corresponding shoulders so as to tip and tilt said platen.

8. In a plotting device having tables for mounting stereoscopic pictures and a stereoscope for, viewing pictures on said tables, index marks comovable in a horizontal plane between the stereoscope and the tables, a tracing implement movable with said index marks, means for raising and lowering said tables, and means for constraining the movements of said index marks so that every position of said marks is parallel to every other position thereof.

thereof. I

10. Ina stereoscopic plotting instrument of y the character described, said instrument being contained in a portable housing, said housing being mounted on casters so that the entire instrument can be supported on a mapping surface and moved thereover, said instrument having a tracing instrument adapted to contact the mapping surface upon which the instrument is supported.

` 11. In combination with a mapping surface, a housing movable bodily over said surface, tables within said housing for mounting stereoscopic pictures, a stereoscope for viewing pictures on' said tables, a support movable over said mapping surface relative to said housing, means constraining the movements of said supportl so that every position'thereof is parallel to every other position, means carried by said support for scanning the stereoscopic model viewed through the stereoscope, and a tracing implement movable with said support for tracing the movements of said support on said mapping surface.

12. In combination with a mapping surface, a housing movable bodily over said surface. tables within said .housing for mounting stereoscopic pictures, a. stereoscope for viewing pictures on said tables, means for adjusting said ltables to compensate for photographic tilt and tip, a support movable over said mapping surface relative to said housing, means constraining the movements of said support so that every position thereof is parallel to every other position, means carried by said support for scanning-the stereoscopic model viewed through'the stereoscope, and a tracing implement movable with said support for tracing the movements of said support .on said mapping surface.

13. .In combination with a mapping surface, a housing movable bodily over said surface, tables within said housing for mounting stereoscopic pictures, a stereoscope for viewing pictures on said tables, said tables being mounted for vertical co-movement, means for moving said tables vertically, releasable means for securing said tables at different heights within the housing, a

escope, and a tracing implement movable with said support for tracing the movements of said support on said mapping surface.

JASPER E. KING. JOHN W. ELLIO'I'I'. 'PHILIP BIKAIL. 

